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Tag: basler camera

To examine the effect of heating up a Basler acA640-100gm on image dark current noise during imaging, I conducted an experiment where I took multiple longer (~2 min) films (conditions: dark room, cap on, constant ambient temperature) with different frame exposure lengths and observed mean image pixel value at the beginning and end of the test. Frame exposure lengths and film durations are approximately equal to the ones used in planetary imaging with this camera and not suitable for DSO imaging.

Image exposure length

With cooler – mean pixel value

Without cooler – mean pixel value

At the beginning of the test

10 ms

17.8

17.5

50 ms

18.1

18.3

500 ms

26.7

26.0

1000 ms = 1 s

44.7

40.1

In the end of the test, after ~2 min when the casing temperature was constant

The following graphs show, the change of camera casing temperature over time in comparison to the constant ambient temperature. From the plots it is observable that majority of heat up occurs in the first 30 sec of imaging and remains almost constant after that.

A few days ago, on New Year’s Day, a sunspot appeared over the western edge of the Sun. AR1944 is huge and actually consist of more than 50 individual sunspots, the largest of them is far larger than the Earth itself. It was possible to observe it using only unaided eye and proper solar filter (e.g. eclipse glasses).

It has been classified as having a beta-gamma-delta magnetic field and these fields are prone to instability that can produce X-class solar flares. During the rotation around the visible limb of the Sun it was quiet and produced only one major X1 flare.

This giant spot is about to rotate off the face of the Sun, this was probably my first and last shot of it. But this is not the only obvious sunspot currently visible on the Sun. I managed to capture a few other.